Automatic gas cut-off



March 22, 1932. ROSS-WATT 1,850,646

AUTOMATIC GAS CUT-OFF Filed March 12, 1950 2 Sheets-Sheet 1 A Inventor G902319 Ross Wafi A iiorney v March 22, 1932.- 55w 1,850,646

AUTOMATIC GAS CUT-OFF Filed March 12, 1930 2 Sheets-Sheet 2 InventorGeorge Ross-Wait A itorney Patented Mar. 22, 1932 UNITED s'rArss PATENToFFrcs GEORGE BOSS-WATT, OF BRONX, NEW YORK AUTOMATIC G48 GUT-OFFApplhation filed March 12,19ao. Serial m. 435,270.

gas cooking ranges but it is to be understood that an automatic cut oilconstructed in accordance with this invention may be used in associationwith any type of gas burners for which the same is found adapted anddesirable.

The primary object of this invention is to provide, in a manner ashereinafter set forth, an automatic gas cut of? which is thermallyactuated and which functions automatically to shut off the supply of gasto the burner should the flame be extinguished as by an interruption inthe supply pipe and which further embodies means whereby the valve willremain closed until manually opened to permit the passage of gas to theburner.

Another important object of the invention is to provide an automatic gascut off of the character set forth which embodies a valve adapted toremain open for the passage of gas to the burner only when said burneris lighted and which further embodies an arrangement which requires thatthe valve be manually retained in open position until the burner islighted.

A still further important object of the invention is to provide anautomatic gas cut off embodying manually operable setting or openingmeans in the form of a spherical knob or handle adapted to prevent thevalve being retained in open position by means other than the hands ofthe operator.

Other objects of the-invention are to provide an automatic gas cut offof the character set forth which may be expeditiously mounted inoperative position for use on a gas range, which will be simple inconstruction, strong, durable, efiicient in its use and which may bemanufactured at low cost.

All of the foregoing and still further objects and advantages oftheinvention may become apparent from a study of the followingspecification, taken in connection with theaccompanying drawings whereinlike characters of reference designate corresponding parts throughoutthe several views, and wherein Figure 1 is a fragmentary view inperspective of one corner portion of a gas range showmg an automatic cutoff device constructed in accordance with this invention mounted inoperative, position thereon.

Figure 2 is a view in vertical longitudinal section showing the cut offvalve in closed position.

Figure 3 is a vertical longitudinal sectional view showing the cut offvalve in open position'to permit the flow of gas to the burner.

Figure 4 is a horizontal sectional view taken substantially on the line4-4 of Figure 3 looking downwardly in the direction indicated by thearrows.

' Referring'to the drawings in detail, the reference character 1designates the top of a conventional gas range having the burner 2 towhich gas is supplied from the pipe 3 through" the medium of the mixingtube 4.

The plpe 3 is in communication with the outlet port 5 located on oneside of a gas chamber 6 formed on themetallio casing or. housing 7 whichis suspended beneath the top 1 of the gas range. The chamber 6 isfurther provided with an inlet port 8 with WhlCll communicates the gassupply pipe 9 which is detachably secured thereto by the coupling collar10. The inner end of the Inlet port 8 is formed to provide a valve seat11 upon which is engageable a reciprocating valve 12 rigidly mounted ona rod 13 which extends slidably through a closure plug 14:

into the casing 7. The plug 14 is provided with suitable packing means15 to prevent leakage of gas around the rod 13 from the chamber 6 intothe casing 7 The end of'the rod within the casing 7 is o erativelyconnected through the medium 0? the pin and slot connection 19 to thelower end portion of a valve retaining lever 20 which is mounted forswingin movement in the casing 7 through the me ium of the shaft 21which is mounted rotatably in the sleeve 22 which projects inwardly fromone of the side walls of the casing 7 The shaft 21 is Iprovided with apolygonal end portion 23 w ich extends through an intermediate portionof the retaining lever which is fixed thereon through the medium of theset screw 24. The upper end portion of the retaining lever 20 is notchedor recessed as at 25 for 0. pur ose which will be presentl set forth.

A t ermal element designate generally byothe reference character 26 issup orted .a ve the burner 2 to be played u on y the flame from saidburner through t e medium of a supporting arm or bracket 27 which isclampe on the mixing tube 4. The thermal actuatin device 26 comprises abody portion 28 aving a longitudinal passage 29 therein whichcommunicates with a cylinder 30 formed in one end thereof. Threaded onthe end of the member 28 in which the cylinder 30 is provided is a tube31 which is filled with mercury and which has mounted :5 therein aperforated plug 32 through which the mercury may pass from the tube 31into the cylinder 30.

An actuating wire or rod 33 extends through the passage 29 into thecylinder 30 and hasfixed thereon the piston 34-mounted for reciprocatorymovement in the cylinder 30. The cable or rod 33 is flexible and extendsslidably through a flexible housing 35 which has one end secured to themember 28 through the medium of the clamp nut 36 and its opposite end.secured to the casing 7 through the medium of the clamping nut 37. Therod 33 projects into a cylindrical opening 38 in the casing 7 with whichthe housing 35 communicates. The head 39 is mounted for sliding movementin the cylindrical opening 38 and is fixed on the end of the rod 33 foractuation thereby. The head 39 is disposed in abutting engagement withthe head 40 which is mounted on the adjacent end of a rod 41 slidablymounted in the supporting brackets 42 and 43 mounted on one of the sidewalls of the casing 7. A collar 44 is fixed on the rod 41 in spacedrelation to the supporting bracket 43 and a coil s ring'45 encirclessaid rod and has one end impinged against said bracket 43 and theopposite end impinged against the collar 44 in a manner to yieldinglyurge the rod 41 and the head .40 into engagement with the head '39 onthe flexible actuating rod 33. The rod 41 is operatively connectedthrough the medium of the, pin and slot connection 46 to the upper endof a pivotally mounted keeper 47 which is mounted for swinging movement,as at 48, in the casing 7. The lower end of the keeper 47 is adapted forengagement in the recess 25 of the valve retaining lever 20 in themanner clearly illustrated in Figure 3 of the drawings for the pur oseof maintaining the valve 12 disengage from. the seat 11. One end of thecasing 7 is provided with an opening 49 whereb access ma be had to theinterior of sai casing an said opening is closed by a removable closureplate 50. As clearly illustrated in Figure 4 of the drawings, theopening 49 extends on one end and one side of the casing and the closureplate 50 is of angular form and secured in place through the medium ofthe screws 51.

In use, when it is desired to light the burner '2 the operator actuatesthe retaining lever 20 through the medium of the s herical knob orhandle 52 fixed on one end 0 the shaft 21 in a manner to swing saidretaining lever 20 to the position indicated in dotted lines in Figure 2of the drawings and in full lines in Figure 3. This moves the valve 12to open position with respect to the seat 11 through the medium of therod 13, as will be obvious, against the tension of the coil spring 18.Gas then flows from the pipe 9 through the chamber 6 and the pipe 3 tothe mixing chamber 4 and the burner 2 and is ignited by the operator.When the flames pla on the tube 31, the mercury therein is heate andexpands and passes through the port in the plug 32 into the cylinder 30of the member 28 in a manner to actuate the piston 34 and the flexiblerod 33. As illustrated to advantage in Figure 3 of the drawings, the rod33 will then move the head 39 inwardly and slide the rod 41 inwardlagainst the tension of the'coil spring 45 an swing the keeper 47 in amanner to engage the same with the upper end of the lever 20 and in thismanner retain the valve 12 in open position. Should the flames from theburner 2 be extinguished, the mercury in the tube 31 will cool andcontract and thus the coil spring 45 will be permited to shift the rod41'in a manner to disengage the keeper 47 from the retaining lever 20and the coil sprin 18 will then move the valve 12 to close position onthe seat 11 and the supply of gas to the burner is thus cut off.

It will thus be seen that I have provided an automatic gas cut oflwhereby the passa e of the gas to the burner is permitted on y when theburner is functioning properl or when the valve is manually maintaine inopen position. The substantially spherical knob or handle 52 willeffectively prevent the valve from being maintained in open posi-' tionby extraneous means by persons who may wish to commit suicide. It isfurther understood that one of the thermal elements 26 is to beoperatively associated with each of the burners on the gas range and thehead 40 on the rod 41 is engageable with the head 39 of the actuatingrod 33 of all of said thermal devices for actuation thereby.

It is believed that the many advantages of an automatic gas cut oilconstructed 1n ac- 5 cordance with this invention will be readilyunderstood, and although the preferred embodiment of the invention is asillustrated and described, it is to be understood that changes in thedetails, of construction may be had' which will fall within the scope ofthe invention as claimed. I k

What is claimed is An automatic gas out 01f for burners com- .prising acasing, a gas chamber mounted on the casing having an outlet port and aninlet port provided with a valve seat, a valve disposed in the chamberand engageable on the seat to close the inlet port, a rod extendingslidably into the chamber from the casing and upon which the valve ismounted, a spring engaged with the rod to yieldingly maintain the valvein closed position, manually operable means for retaining the valve inopen position comprising a retaining lever mount- 5 ed for swingingmovement in the casing and operatively connected to the rod, anactuating handle located exteriorly of the casing and connected to thelever for manually swinging the same, a keeper mounted for swingingmovement in the casing and engageable with the retaining lever tomaintain the same in operative position, thermally actuated means forshifting the keeper to permit the spring to release the same, said meanscomprising a body member, said body member having a cylinder formedtherein, a passage extending longitudinally therethrough andcommunicating with'the inner end of t 9 cylinder, a mercury filled tubeclosed at one 40 end mounted on the body member and communicating withthe c linderto permit the passage of the mercury rom the container intosaid cylinder, means for mounting the body member and the containerabove 5 the burner in the path of the flames therevfrom, a pistonmounted for reciprocatory movement in the cylinder, a housingcommunicating with thel-passage in the body member and the interior ofthe, casing, a rod mounted for sliding movement through the housing andhavin one end extending into the cylinder and xed to the piston therein,a head fixed on the opposite end of the rod and mounted for slidingmovement in the casing, a spring controlled rod mounted for slidingmovement in the casin and having a head thereon engageable wit the saidhead for actuation thereby, said spring controlled rod being operativelyconnected to the keeper.

In testimony whereof I afix m signature.

GEORGE ROS -WATT.

